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NEW YORK: The coronavirus still has a long way to go. That's the message from a crop of new studies across the world that are trying to quantify how many people have been infected. Official case counts often substantially underestimate the number of coronavirus infections. But in new studies that test the population more broadly, the percentage of people who have been infected so far is still in the single digits. The numbers are a fraction of the threshold known as herd immunity, at which the virus can no longer spread widely. The precise herd immunity threshold for the novel coronavirus is not yet clear; but several experts said they believed it would be higher than 60%. Even in some of the hardest-hit cities in the world, the studies suggest, a vast majority of people still remain vulnerable to the virus. Some countries — notably Sweden, and briefly Britain — have experimented with limited lockdowns in an effort to build up immunity in their populations. But even in … [Read more...] about Covid-19: The world is still far from herd immunity for coronavirus

By Nadja Popovich and Margot Sanger-Katz The coronavirus still has a long way to go. That’s the message from a crop of new studies across the world that are trying to quantify how many people have been infected. Official case counts often substantially underestimate the number of coronavirus infections. But in new studies that test the population more broadly, the percentage of people who have been infected so far is still in the single digits. The numbers are a fraction of the threshold known as herd immunity, at which the virus can no longer spread widely. The precise herd immunity threshold for the novel coronavirus is not yet clear; but several experts said they believed it would be higher than 60%. Even in some of the hardest-hit cities in the world, the studies suggest, a vast majority of people still remain vulnerable to the virus. Some countries — notably Sweden, and briefly Britain — have experimented with limited lockdowns in an effort to build up … [Read more...] about The world is still far from herd immunity for coronavirus